1. Field of the Invention
The present invention relates to distributed antenna systems in telecommunications networks.
2. Description of the Prior Art
The modular design of a high power, low Passive InterModulation (PIM), base station management interface for Distributed Antenna System (DAS) applications in telecommunications networks is designed for use in the telecommunication industry. A typical deployment of a Base Telecommunication Station (BTS) in the telecommunication industry is designed for high Radio Frequency (RF) power input signals. The high RF power signal provides the necessary RF power to provide both coverage and capacity in a telecommunications network and is often associated with a macro-network solution that supports high RF power antennas. In a DAS deployment, however, the goal of the network solution is to add coverage and capacity to an area where the antenna RF signal is weak or cannot be accessed, for example inside a tunnel, a stadium or an airport; that is, either in a building or outdoor. Also, DAS deployments are typically used in areas where the antennas are in close proximity to the public (UE). As a result, the RF power of the antenna must be kept low to meet minimum radiated emissions standards determined by the Federal Communications Commission (FCC). Therefore, DAS deployments utilize a low RF power signal that is used in conjunction with low RF power antennas. The RF signal is also required to have very low levels of PIM. PIM levels that are too high can cause interference in the low RF power signals in the antenna receive (Rx) path, resulting in a multitude of issues inside telecommunication networks. To this end it becomes necessary to have an interface between the BTS and the DAS that can adjust the signal input RF power level from the BTS to signal output RF power levels that are harmonious with the requirements of a DAS while inducing very low PIM levels into the attenuated RF signal.